Two B-52 bombers flew through airspace recently claimed by China as part of its territorial air defense zone.
The flights happened Monday.
A defense department official says the B-52s were not armed and flew as part of a long-planned flight.
He says the Chinese did not challenge the US bombers in any way.
The Wall Street Journal reports the B-52s took off from Guam and flew over islands claimed by both China and Japan.
The Chinese recently claimed a large chunk of the airspace near the islands as their own and said today its air defenses had monitored the bombers as they flew nearly two-and-a-half hours in the disputed airspace.
The US has two bases that are home to B-52s - Minot and Barksdale.
Currently, B-52s from Barksdale are on assignment to Guam to provide a bomber presence in that region.